On a system configured to use Amazon S3 blob storage, you may see errors in the logs indicating that the S3 connection pool has run out of resources.
2020-09-17 16:54:19,429+0000 WARN [qtp143422335-624] *UNKNOWN org.sonatype.nexus.repository.httpbridge.internal.ViewServlet - Failure servicing: GET /nexus/repository/myrepo/file.xml
com.amazonaws.SdkClientException: Unable to execute HTTP request: Timeout waiting for connection from pool
There was a new property introduced in 3.20 which allows you to increase the size of the S3 connection pool. If you are encountering these errors in your logs we recommend adding this property to the $data-dir/etc/nexus.properties file.
A value of 200 has been sufficient to resolve these errors. Setting this parameter to a higher value may introduce performance problems.
You will need to restart Nexus for this change to take effect.